An investigation of the inscriptions on the two Tang Dynasty jade Buddhas’ substrates in the Guanghui Temple in Zhengding, Hebei, reveals that the two lines newlycarved Buddha statues were enshrined and worshipped at the Longxing Temple in Hengzhou, which happeat the Longxing Temple in Hengzhou, which happened to agree with the relevant records in The Essentials of Law and Regulations of the Tang Dyniasty. These Buddha statues prove in a physical form for the first time that the system of the imperial death anniversary prayer service started in the 81 state including the states of Tong and Hua as early as the 15th year of the imperial title of Kaiyuan (727 AD). The 9 imperial death anniversaries to the former emperors and empresses in the 15th and 16th years of Kaiyuan recorded in the inscriptions were listed chronologically in the two years but not in their reigns, which indicated the practical performance of the imperial death anniversary prayer service by local officials. In the 11th year of the imperial title of Zhenyuan, because of the ruin of the worship hall, the line of Buddha statues alongside the west wall were temporarily moved to the temples dinning hall. “Zhishao the monk of the Kaiyuan Temple” was appointed as the “supervisor of rebuilding” of the Longxing Temple. This showed the power of control of the Kaiyuan Temple as the state official temple over other temples in the state.

Buddhism in the Tang Dynasty; the Guanghui Temple; inscriptions on the jade Buddha statue; the imperial demise anniversary prayer service; official Buddhist temple